I don´t want automate Rhino from an external application... :) I started with programming my first plug in. It´s a beginner question: Is the only way to test the program to compile it as plug in and load it to rhino, or is there a possibility to test parts of the program direct as console application. What is the usual work flow, for testing small parts.

If you are not automating Rhino, then you will not be creating a console application. You will be creating a Rhino plug-in, which is a .NET Assembly that references RhinoCommon.dll and has a Rhino.PlugIns.PlugIn-inherited class.

To create a plug-in, first download the RhinoCommon templates for Rhino 5:

Thanks, I installed the Rhino Common templates for Visual Studio, and made a small plug in, but I am beginner and I test my “program” every minute and it takes a lot of time to debug it, and therefore my question.